① Short-term balance. Pay-as-you-go system usually keeps the balance of the fund for one year or several years, which is flexible and can be adjusted at any time according to the changes of the situation.

② Pay attention to fairness. The primary goal of social security is to maintain social equity. Pay-as-you-go system has the characteristics of intergenerational redistribution and economic mutual assistance, and has obvious fairness.

③ Low management cost and low risk. Pay-as-you-go system does not have much capital accumulation and does not need too much cost. At the same time, you don't have to worry about the losses caused by risk factors such as economic fluctuations, inflation and interest rate changes.